Research On Application Of Lysine?Arginine Improving The Quality Properties Of Pork Sausage

In recent years,it was found that amino acids can improve the quality characteristics of meat products.In this paper,different levels of L-Lys and L-Arg were used to study their effects on the quality characteristics of pork sausage and mechanism were investigated.Further,we extracted myosin of pork and added a certain proportion of L-Lys/L-Arg to determine the change of the myosin solubility.The mechanism of L-Lys/L-Arg changing solubility of protein was investigated by hydration,surface hydrophobicity,transfer free energy and zeta potential.The main results were as follows:1.Effect of L-Lys/L-Arg on quality characteristics of pork sausage(1)The addition of 0.6% L-Lys/L-Arg can significantly improve the a* value of(p<0.05),reduce b* value(p<0.05)of pork sausage and give the product a good color.It can also significantly improve the water holding capacity(WHC)(p<0.05),reduce the cooling loss(CL)of pork sausage(p<0.05)and improve the texture characteristics of the product and the three-dimensional network structure of pork sausage gel becomes more uniform and dense.(2)L-Lys/L-Arg can increase the thermal denaturation temperature and strengthen the thermal stability of myosin,and then affect the structure and properties of the product.2.Effect of L-Lys/L-Arg on solubility of pork myosin(1)The addition of L-Lys/L-Arg can make the myosin fibril dissociation,can significantly improve the proportion of monomer myosin solution,improve the solubility of myosin.(2)The addition of L-Lys/L-Arg increased the electric potential of myosin solution and strengthened the repulsion force between particles.The change in charge,increase of the binding sites of water and enhancement of hydration destroyed the aggregation of existing myosin which resulted in the dissociation of filament in a relatively stable state and the myosin solubility increased.(3)The addition of L-Lys/L-Arg increased the hydrogen bonding interactions between myosin and water.Hydrophobic groups occupied the major part of the myosin surface which result in the decrease of intermolecular attraction.Myosin was surrounded by a certain number of hydrophobic groups.Increase of hydrophobic groups increased hydrophobic interaction and improved the van der waals,force between hydrophobicresidues which enhanced the myosin stability.(4)The addition of L-Lys/L-Arg increased the hydrophobic effect and L-Lys/L-Arg could be better combined with the hydrophobic side chains of myosin nonpolar amino acids.Interfacial tension was necessary for the surface of myosin to form solvent interface.Amino acid guanidine residues were attracted to the surface of myosin and the repulsion force produced,which leads to the change of solubility.